604 
FXUS65 KPSR 012344 AAA
AFDPSR

Area Forecast Discussion
Naional Weather Service Phoenix AZ
444 PM MST Mon Nov 1 2021

.UPDATE...Updated Aviation Discussion.

.SYNOPSIS... 
Dry conditions will prevail this week. Temperatures remain fairly
consistent over the next few days as a fair amount of high clouds
pass overhead today and tomorrow. Towards the weekend, a subtle 
drop in temperatures is expected as a dry weather system skirts by
to the north.

&&

.DISCUSSION...
Today's tranquil start to November is the result of generally 
zonal flow aloft. An approaching shortwave would otherwise pass 
through the region today and tomorrow unnoticed if not for the 
increased patches of high clouds right now and the dense high 
clouds lurking off to the west. Temperatures will remain fairly 
persistent as afternoon highs settle near seasonal normals in the 
low to mid 80s today. The Imperial Valley should be on the lookout
for early morning fog again conditions remain favorable for moist
Gulf of California air to surge northward over the cooler desert
environment.

The tranquility will continue for the next several days and skies
will become mostly clear by Wednesday. High pressure ridging will
become more amplified over the Intermountain West late this week 
as a modestly strong shortwave approaches the PNW. Cluster tools 
provide good confidence that our area will see H5 increases up 
towards 586-589 dm by the weekend. This should help surface 
temperatures warm by a few degrees with lower desert highs 
reaching the 85 to 89 degree range this weekend. Right now, 
Sunday appears to be the warmest day in the forecast period, 
nearly 5 degrees or so above seasonal normals.

Variability increases within guidance beyond the weekend as 
ensembles keep wanting to bring the aforementioned shortwave 
energy into the West early next week. Confidence for any 
particular outcome is low, but for the most part, any onshoring of
the wave should support some sort of cooling trend as heights 
decrease, and at least one or two days with noticeable breeziness 
as the pressure gradient tightens. Indications for rain remain 
nearly non-existent, and any that do show up, continuously live in
the day 9 to day 10 range.

&&

.AVIATION...Updated at 2344Z

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: Current 
light westerlies to transition to a period of light/variable winds 
before the overnight easterlies arrive (between 04z and 06z this 
evening). Light easterly winds to persist until 20-21Z on Tuesday, 
then switch to westerly through the rest of the afternoon/early 
evening hours. Speeds will remain light and mostly AOB 8 kts for all 
periods. FEW-SCT mid/high cloud decks (mainly AOA FL120) to prevail 
through the TAF period.

Southeast California/Southwest Arizona including KIPL and KBLH: 
Wind directions will follow typical diurnal tendencies for the
next 24 hours while speeds remain light and mostly AOB 9 kts for 
all periods. A few hours of low stratus and/or fog cannot be ruled
out for KIPL tomorrow morning between 12z to 16z. The potential 
for IFR conditions during that time is 10 percent. Otherwise, 
periods of dense high clouds will continue to filter through. 

&&

.FIRE WEATHER...
Wednesday through Sunday: 
Dry and warm conditions are expected through the forecast period.
Winds will generally be light and favor diurnal patterns. 
Humidity values will trend down slightly, with widespread 
afternoon values in the teens and only modest overnight recovery 
into the 20-50% range. No rain chances at this time.

&&

.SPOTTER INFORMATION STATEMENT... 
Spotters should follow standard reporting procedures.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&

$$

DISCUSSION...12
AVIATION...Percha/12 
FIRE WEATHER...Iniguez